This section provides background information related to the present disclosure which is not necessarily prior art.
Due to ever increasing concerns relating to vehicle fuel efficiency, increased efforts are being expended to reduce the overall weight of a vehicle. Improved vehicle handling and stability are also desired in combination with the reduction in weight.
Some vehicle manufacturers have successfully constructed a number of vehicle structural components from lighter weight materials including magnesium or aluminum alloys. Carbon fiber and reinforced plastic panels have also been incorporated within the vehicle design. This approach, however, may not be possible for certain applications where the component is subjected to substantial mechanical loading. Examples of such components may include vehicle frame members, suspension components, and axle housings.
Some vehicle frame members are constructed from “C”-shaped channels welded to one another. The channels are constructed from a relatively low carbon steel. Several brackets, gussets, flanges, and cross-members may be attached to the vehicle frame rail to provide attachment points for various vehicle body and suspension components that are not exactly aligned with the longitudinally extending frame rails.
Attempts have been made to hydroform hollow steel tubes to produce vehicle frame rails. While some of these attempts have been successful, limits on the amount of expansion that may be obtained by hydroforming exist. Some manufacturers have added additional procedural steps and off-line machines to bend, crush or otherwise deform a portion of the frame rail. While these additional sets of tools and process steps may more closely define a frame rail to a desired shape, the costs associated with these manufacturing techniques may be exorbitant. Accordingly, a need exists in the art to provide a manufacturing process for cost efficiently providing a reduced weight structural member having relatively complex geometry.